Re: [syzbot] [ext4?] kernel BUG in ext4_enable_quotas

Jan Kara
2024-02-12T13:23:52Z

On Sat 10-02-24 06:59:05, syzbot wrote:
> syzbot suspects this issue was fixed by commit:
>
> commit 6f861765464f43a71462d52026fbddfc858239a5
> Author: Jan Kara <jack@suse.cz>
> Date: Wed Nov 1 17:43:10 2023 +0000
>
> fs: Block writes to mounted block devices
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147e5b20180000
> start commit: 89bf6209cad6 Merge tag 'devicetree-fixes-for-6.5-2' of git..
> git tree: upstream
> kernel config: https://syzkaller.appspot.com/x/.config?x=1b32f62c755c3a9c
> dashboard link: https://syzkaller.appspot.com/bug?extid=693985588d7a5e439483
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11ba1fefa80000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1636640fa80000
>
> If the result looks correct, please mark the issue as fixed by replying with:

The syzbot reproducer seems to mess with multiple ext4 mounts stacked on
one another and the loop device as well. Quite likely it managed to corrupt
the mounted filesystem. So:

#syz fix: fs: Block writes to mounted block devices

Honza
--
Jan Kara <jack@suse.com>
SUSE Labs, CR